An embodiment of the present invention relates generally to integrated circuit fabrication. More particularly, an embodiment of the present invention relates to electrical connection technology. In particular, an embodiment of the present invention relates to a ball-limiting metallurgy comprising a tin diffusion barrier layer.
Description of Related Art
Electrical bump connectors such as metal bumps or balls are used in flip-chip (C4) applications. As the progress of miniaturization continues, the sizes of individual metal grains at the junction between a microelectronic device metallization and the electrical bump become increasingly large relative to the mass of the electrical bump. Consequently, junction disparities have an increasingly detrimental effect on electrical communication between the device and the electrical bump. One junction disparity relates to migration of bump metals through the metal layer that is disposed over the metallurgy. Another consequence of miniaturization is stress that builds up in the ball-limiting metallurgy due to the formation of intermetallic pockets between the metallization and the electrical bump.